Are You Confident of the Diagnosis?
What you should be alert for in the history
Talon noire is an asymptomatic condition of post-traumatic intraepidermal hemorrhage, arising predominantly in the young athlete. It is observed almost exclusively in sports associated with repetitive jumping or abrupt turning of the feet, including basketball, tennis, lacrosse, and football.
An analogous condition, termed black palm, may be observed in racket sports, gymnastics, and golf. In rare cases, lesions may result from nonathletic activities, such as self-inflicted hammer wounds. Contact with hot sand and friction from the nonslip edge of a swimming pool have produced similar lesions on the sole of the foot. Regardless of etiology, lesions invariably appear on the acral skin of the hands and feet following some form of trauma.
Characteristic findings on physical examination
Lesions are comprised of multiple brown-black or blue-black petechiae, which coalesce to form a central hyperpigmented macule or patch surrounded by scattered satellite lesions (Figure 1).
Characteristically, the lesions are horizontally oriented on the posterior or posterolateral aspect of the heel, just superior to the hyperkeratotic edge of the plantar surface. The lesions tend to be unilateral and measure up to 3cm. The affected area is not elevated, depressed, or indurated. It is not palpable.
Lesions that do not coincide with the aforementioned distribution have been observed on the sole of the foot or medial aspect of the heel. Furthermore, circular or oval lesions may be seen. Lesions associated with a callus have also been reported; however, it is the authors’ opinion that the callus is unrelated to the underlying disease process as callosities are common on this part of the heel.
Expected results of diagnostic studies
A hyperkeratotic stratum corneum consistent with an acral site is seen. Loss of the granular layer and parakeratosis may also be present. Within the stratum corneum, there are rounded collections of blood. In addition to these “lakes of hemorrhage,” dilated capillaries and collections of extravasated red blood cells are seen in the papillary dermis. Occasionally, coagulated blood can be seen within the lumina of the intracorneal portion of the eccrine sweat ducts.
Histochemically, benzidine stains are positive, proving the pigment is derived from hemoglobin.Extravasated red blood cells in the stratum corneum are protected from phagocytes. Thus, hemosiderin is not produced and traditional iron stains such as Prussian blue are negative.
Differential diagnosis and diagnostic confirmation
The differential diagnosis includes benign nevi, malignant melanoma, traumatic tattoo, and verruca.
Talon noire may be mistaken for a wart, particularly if the clinical picture is complicated by the coexistence of a callus. Indeed, the petechiae of talon noire bear resemblance to the thrombotic capillaries of the wart, although the linear configuration makes the latter less likely. If the diagnosis remains unclear, the lesion should be pared down with a surgical blade in an effort to identify underlying wart tissue. As the surface keratin is removed, specks of dried blood will be present in the shavings; however, the pinpoint bleeding from the tips of elongated papillae, as seen in the setting of verruca vulgaris, will be absent.
To the untrained eye, talon noire may resemble melanoma; however, close inspection will reveal that the lesion is comprised of an aggregate of smaller punctuate lesions. A history of recent strenuous activity, coinciding with the appearance of the lesion, gives further credence to the idea that the lesion is benign. For the patient who demands physical evidence, the presence of the characteristic specks of dried blood in the scraping can be particularly convincing.
A traumatic tattoo results from the deposition of foreign material into the skin. This diagnosis should be entertained if there is a history of penetrating trauma. Common agents include gunpowder, carbon, lead, dirt, and asphalt. Paring may or may not remove the pigment, depending on the depth of penetration through the epidermis and dermis.
Other remote considerations include eschar, gangrene, vasculitis, anthrax, terra firma dermatosis (dirt on the skin), warfarin necrosis, tinea nigra, calciphylaxis, and hemangiomas.
The diagnosis of talon noire can be made on the basis of the history and physical examination alone. If the diagnosis remains in doubt, however, biopsy is indicated. Alternatively, the pared shavings can be sent to pathology for benzidine staining. If one wishes to forgo a pathologic diagnosis, a stool guaiac or Hemoccult test can be performed in-office on the pared shavings.
Who is at Risk for Developing this Disease?
Talon noire is a condition seen predominantly in athletic adolescents and young adults without gender predilection. With few exceptions, patients fall into the 12-24 age range. A study of 596 healthy young athletes identified an incidence of 2.85%.
What is the Cause of the Disease?
Repetitive pounding on hard surfaces or sudden directional changes produce a shearing stress sufficient to disrupt vulnerable capillaries in the papillary dermis. Extravasated erythrocytes are eliminated transepidermally to the stratum corneum through sweat ducts, which provide the path of least resistance. Once in the stratum corneum, these erythrocytes coalesce to form lakes of hemorrhage. These lakes of hemorrhage represent the pigmentation seen in talon noire.
Systemic Implications and Complications
Talon noire has no systemic implications.Treatment options
Treatment options are summarized in Table I.
|Physical Modalities||Shoe with adequate medial arch support and cushion|
|Gel heel cup|
|Surgical Treatment||Paring the lesion|
Optimal Therapeutic Approach for this Disease
Once the diagnosis is made, no treatment is necessary. Talon noire will resolve spontaneously; however, complete resolution may be delayed until 4-6 weeks after cessation of the causative activity.
To satisfy the patient who demands faster resolution, the lesion may be pared down to remove pigment.
To prevent recurrence, we recommend properly fitting footwear with adequate arch support and cushion. The use of a heel gel cup or felt pad may also be helpful. Again, it is the authors’ opinion that these steps are unnecessary as this is a benign entity that is painless, leads to no complications, and resolves spontaneously.
It is necessary to reassure the patient and family of the benign nature of talon noire and to see the patient back for follow-up 4-6 weeks after the end of the sport season to ensure complete resolution.
Unusual Clinical Scenarios to Consider in Patient Management
Although the diagnosis of talon noire is straightforward clinically and histologically, in the event of any uncertainty of the clinical appearance, a biopsy is warranted, with the special concern of ruling out an acral lentiginous melanoma.
What is the Evidence?
Urbina, F, Leon, L, Sudy, E. “Black heel, talon noire, or calcaneal petechiae?”. Australas J Dermatol. vol. 49. 2008. pp. 148-51. (A case series of six patients with superficial cutaneous hemorrhages of the feet. The authors describe a classical case of talon noire and several atypical lesions which differ in production mechanism, morphology, and location.)
Wilkinson, DS. “Black heel a minor hazard of sport”. Cutis. vol. 20. 1977. pp. 393-6. (A review of epidemiologic data and relation to sports)
Apted, JH. “Calcaneal petechiae (black heel)”. Australas J Dermatol. vol. 14. 1973. pp. 132-5. (A case report describing a 15-year-old male football player with talon noire and the histopathologic findings of a punch biopsy specimen)
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